Method of making sanitary napkin having improved flap disposition and means for maintaining the flap therein

ABSTRACT

Disclosed is a sanitary napkin having flaps folded over the topsheet. This arrangement helps to maintain the topsheet in a sanitary condition and is more convenient for the wearer than a configuration having the flaps folded over the backsheet. The flaps may be maintained in this folded arrangement by a unitary release strip which bridges the flaps and covers any adhesive used to attach the flaps to the undergarment. If desired, the release paper may further wrap the longitudinal side margins of the sanitary napkin to additionally cover adhesive disposed on the central portion of the backsheet. If desired, the flaps may be folded over the topsheet, overlap each other and be adhesively joined to the other flap.

This is a continuation of application Ser. No. 08/687,845, filed on Jul.26, 1996, now abandoned, which is a division of application Ser. No.08/437,251 filed on May 8, 1995, which is a continuation of applicationSer. No. 08/082,894, filed on Jun. 25, 1993, abandoned; which is acontinuation of application Ser. No. 07/960,574, filed on Oct. 13, 1992,abandoned; which is a continuation of application Ser. No. 07/732,442,filed on Jul. 18, 1991, abandoned; which is a continuation ofapplication Ser. No. 07/517,104, filed on May 1, 1990, abandoned.

FIELD OF THE INVENTION

This invention is directed to sanitary napkins, and particularly tosanitary napkins having flaps. More particularly, this invention isdirected to the packaging of such sanitary napkins prior to first use bythe wearer.

BACKGROUND OF THE INVENTION

Sanitary napkins having flaps extending outwardly from the longitudinalside margins are well known in the art. For example, U.S. Pat. Nos.4,589,876 issued May 20, 1986, to Van Tilburg and 4,687,478 issued Aug.18, 1987, to Van Tilburg disclose preferred sanitary napkins with flapsand are incorporated herein by reference to illustrate particularlypreferred flapped sanitary napkin constructions.

To conserve space during packaging, i.e., the period between manufactureof the sanitary napkin and its intended first use by the wearer, theflaps of such sanitary napkins are typically folded to overlay thebacksheet. At the time of the first use by the wearer, the flaps areusually unfolded to facilitate installation of the sanitary napkin intothe wearer's undergarment. Typically adhesive, interposed between thebacksheet and the flap adhesive release paper, is used for maintainingthe flaps in the folded disposition prior to the wearer's first use ofthe sanitary napkin.

Several attempts have been made to provide alternative means formaintaining the flaps in the desired disposition prior to first use ofthe sanitary napkin by the wearer. For example, U.S. Pat. No. 4,759,754issued Jul. 26, 1988, to Korpman discloses an adhesive tab which can beused for maintaining the flaps in the desired disposition overlaying thebacksheet during packaging. U.S. Pat. No. 4,701,178 issued Oct. 20,1987, to Glaug et al. discloses a sanitary napkin having a singlerelease strip which covers the centrally located adhesive of thebacksheet and over which release strip the flaps are folded.

However, none of these attempts to improve packaging prior to the firstuse by the wearer have proven entirely satisfactory. For example, thewearer is typically concerned with maintaining the cleanliness, sanitarycondition and appearance of the sanitary napkin's body contactingtopsheet, rather than that of the sanitary napkin's garment contactingbacksheet.

Further, when the wearer installs the sanitary napkin into herunderwear, the sanitary napkin is typically in the wearing position,with the topsheet facing the wearer, while she manipulates the flaps andrelease strip. There can be an inconvenience associated withmanipulating flaps and any associated release strip which are foldedover the backsheet. Flaps folded over the backsheet are behind andobscured by the sanitary napkin, so that the flaps cannot be seen whilethe wearer is attempting to install the sanitary napkin to herundergarment. Also, flaps folded over the backsheet have a tendency tobecome adhered to the adhesive of the backsheet, unless held apart.

Accordingly, it is an object of this invention to overcome certainproblems of the prior art. Particularly, it is an object of thisinvention to provide a flap disposition which promotes the cleanlinessof the topsheet of the sanitary napkin during packaging and handling bythe wearer prior to the first use of the sanitary napkin. Additionally,it is an object of this invention to provide a convenient means formanipulating the flaps from the packaged arrangement to the dispositionwhich the flaps will be used during wear. Finally, it is an object ofthis invention to provide a effical process for making a sanitary napkinaccording to this invention.

BRIEF SUMMARY OF THE INVENTION

This invention comprises a sanitary napkin having and generally boundedby two longitudinal and two lateral side margins. The sanitary napkinhas a liquid pervious topsheet, a liquid impervious backsheet that is atleast partially peripherally joined to the topsheet, and an absorbentcore between the topsheet and the backsheet. A flap extends laterallyoutwardly from each longitudinal side margin of the sanitary napkin andis folded over to the topsheet prior to the first use of the sanitarynapkin by the wearer.

Several means are available for maintaining the flaps in thisdisposition. For example, flaps are typically provided with adhesive onthe face of the flaps which is generally coextensive of the backsheet,and which adhesive is used to releasably affix the flaps to theundergarment of the wearer. A very suitable means for maintaining theflaps in the folded disposition having a topsheet facing relationship isa unitary release strip bridging such adhesive of the flaps.

BRIEF DESCRIPTION OF THE DRAWINGS

While the Specification concludes with claims particularly pointing outand distinctly claiming the present invention, it is believed theinvention will be better understood from the following description takenin conjunction with the accompanying drawings wherein like parts aregiven the same reference numeral, analogous parts are designated with aprime symbol, related parts are designated by alphabetic characters,adhesive is shown in phantom and:

FIG. 1 is a top plan view, shown partially in cutaway, of a sanitarynapkin according to the present invention;

FIG. 2 is a top plan view of a sanitary napkin according to the presentinvention having a unitary release strip bridging the flaps;

FIG. 3 is a top plan view of a sanitary napkin having an H-shapedrelease strip bridging the flaps and shown partially unwrapped forclarity;

FIG. 4 is a vertical sectional view taken along line 4--4 of FIG. 3;

FIG. 5 is a vertical sectional view of a sanitary napkin according tothe present invention having overlapping flaps; and

FIG. 6 is a schematic view of one apparatus which may be utilized tomake a sanitary napkin according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1, the invention comprises a disposable absorbentarticle, particularly a sanitary napkin 20. The sanitary napkin 20 isused to collect vaginal discharges, such as menses, and prevent soilingof the wearer's clothing by such discharges. The sanitary napkin 20features a liquid pervious topsheet 22, a liquid impervious backsheet24, an absorbent core 26 intermediate the topsheet 22 and the backsheet24 and at least one flap 28 extending from a longitudinal side margin 30of the sanitary napkin 20, and preferably two symmetrically oppositeflaps 28, one extending from each longitudinal side margin 30 of thesanitary napkin 20. The perimeter of the sanitary napkin 20 is definedby two longitudinal side margins 30 and two lateral side margins 32.

Associated with the sanitary napkin 20 is a means, such as adhesive, forreleasably affixing the sanitary napkin 20 to the undergarment of awearer. More particularly, each flap 28 may have its own adhesive patch40. Preferentially, such adhesive 40 is associated with the face of theflap 28 which contacts the undergarment of the wearer. Also the centralportion of the sanitary napkin 20 intermediate the flaps 28 may haveadhesive 42 associated with the area of the central portion of thesanitary napkin 20 which contacts the undergarment of the wearer.Preferentially such adhesive 42 is joined to the outwardly oriented faceof the backsheet 24.

The sanitary napkin 20 has a longitudinal centerline 34 whichconceptually divides the sanitary napkin 20 into two substantiallysymmetrically opposite halves. As used herein the term "longitudinal"refers to an imaginary line, axis or direction of the sanitary napkin20, which line, axis or direction is typically centered between thelongitudinal side margins 30 of the napkin and is generally aligned withthe vertical plane which bisects a standing wearer into left and rightbody halves. The term "lateral" refers to an imaginary line, axis ordirection generally orthogonal the longitudinal direction, within theplane of the sanitary napkin 20, and is generally sideways alignedrelative to the wearer.

Examining the components in more detail with continuing reference toFIG. 1, the topsheet 22 is the component of the garment which isoriented towards and contacts the body of the wearer, and receivesbodily discharges. The topsheet 22 is liquid pervious and should beflexible and nonirritating to the skin. As used herein the term"flexible" refers to materials which are compliant and readily conformto the shape of the body or respond by easily deforming in the presenceof external forces. Preferably the topsheet 22 is not noisy, to providediscretion for the wearer. The topsheet 22 should be sanitary, clean inappearance and somewhat opaque to hide the bodily discharges collectedin and absorbed by the core 26.

The topsheet 22 should further exhibit good strikethrough and rewetcharacteristics, permitting bodily discharges to rapidly penetrate thetopsheet 22 to the core 26, but not flow back through the topsheet 22 tothe skin of the wearer. Suitable topsheets 22 may be made from nonwovenmaterials or perforated polyolefinic films.

The topsheet 22 has a plurality of apertures to permit liquids depositedthereon to pass through to the core 26. Such apertures may, but neednot, be present in the flaps 28. An apertured polyolefinic film topsheet22 having about 5 to about 60 percent open area, typically about 25percent open area, and a thickness of about 0.01 to about 0.05millimeters prior to aperturing and about 0.46 to about 0.51 millimetersafter aperturing is suitable.

If desired, the topsheet 22 may be sprayed with a surfactant to enhancefluid penetration to the core 26. The surfactant is typically nonionicand should be nonirritating to the skin. A surfactant density of about0.01 milligrams per square centimeter of topsheet 22 area is suitable. Asuitable surfactant is sold by the Glyco Chemical, Inc. of Greenwich,Conn. as Pegosperse 200 ML.

A particularly suitable topsheet 22 may be made in accordance with U.S.Pat. No. 4,342,314 issued Aug. 3, 1982 to Radel et al. and U.S. Pat. No.4,463,045 issued Jul. 31, 1984 to Ahr et al., which patents areincorporated herein by reference for the purpose of disclosingparticularly preferred executions of liquid pervious topsheets. Atopsheet 22 made of model X-3265 or model P1552 apertured formed filmsold by the Ethyl Corporation, Visqueen Division, of Terre Haute, Ind.has been found to work well.

The backsheet 24 may be any flexible, liquid resistant, preferablyliquid impervious material, such as a polyolefinic film. The backsheet24 prevents discharges collected by and contained in the sanitary napkin20, and particularly discharges absorbed by the core 26, from escapingthe sanitary napkin 20 and soiling the clothing and bedding of thewearer. Preferably the backsheet 24 is not noisy, to provide discretionfor the wearer.

The backsheet 24 may also be impervious to malodorous gases generated byabsorbed bodily discharges, so that the malodors do not escape andbecome noticed by the wearer. A low density polyethylene backsheet 24about 0.01 to about 0.05 millimeters in thickness, preferably about 0.02millimeters in thickness, has been found to work well. A polyethylenefilm, such as is sold by the Ethyl Corporation, Visqueen Division, undermodel XP-39385 has been found particularly well suited for the backsheet24.

Further, the backsheet 24 may be made of a soft clothlike material whichis hydrophobic relative to the topsheet 22, e.g., a polyester orpolyolefinic fiber backsheet 24 works well. A particularly preferredsoft, clothlike backsheet 24 material is a laminate of a polyesternonwoven material lamina and a film such as described in theaforementioned U.S. Pat. No. 4,476,180 issued to Wnuk.

In a particularly preferred embodiment, the backsheet 24 is slightlylarger than the topsheet 22 and the intermediate absorbent core 26. Insuch an embodiment, the topsheet 22 and intermediate absorbent core 26are peripherally circumscribed by the backsheet 24 which has a radialmargin of about 0.5 centimeters to about 1.5 centimeters, preferablyabout 1.0 centimeter, from the side margins of the topsheet 22. Thisgeometry provides a marginal area of protection should the core 26become overloaded or the sanitary napkin 20 otherwise fail. In such anembodiment the backsheet 24 and flaps 28 are preferably unitary andcoextensive.

The topsheet 22 and the backsheet 24 are preferentially peripherallyjoined using known techniques, either entirely so that the entireperimeter of the sanitary napkin 20 is circumscribed by such joinder orare partially peripherally joined at the perimeter. The term "Joined"refers to the condition where a first member or component is affixed, orconnected, to a second member or component either directly; orindirectly, where the first member or component is affixed, orconnected, to an intermediate member or component which in turn isaffixed, or connected, to the second member or component. The joinedcondition between the first member, or component, and the second member,or component, is intended to remain for the life of the sanitary napkin20. Conversely, components are considered "removably affixed" if thecomponents may be detached and separated from each other withoutdestruction or unintended gross deformation of either.

Any joined arrangement that provides for capture of the core 26intermediate the topsheet 22 and the backsheet 24 and a unitary assemblyis suitable. Such an assembly has two mutually opposed major faces, onedefined by the topsheet 22 and one defined by the backsheet 24.

The outwardly oriented face of the backsheet 24 may further comprisemeans 42 for attaching the sanitary napkin 20 to the undergarment of thewearer. Pressure sensitive adhesive 42 has been commonly found to workwell for this purpose. Preferably a strip of longitudinally orientedadhesive 42 provides good protection against either the front or theback of the sanitary napkin 20 becoming detached from the wearer'sundergarment. The adhesive strip 42 may be continuous or intermittent. Aparticularly preferred arrangement utilizes two longitudinally orientedstrips 42, one on each side of the longitudinal centerline 34.

The absorbent core 26 is the means for collecting and containing bodilydischarges, particularly menses, deposited thereon or which otherwisetraverses through the liquid permeable topsheet 22. The core 26 is thecomponent of the sanitary napkin 20 which receives and retains thebodily discharges. The core 26 is conformable and nonirritating to theskin. The core 26 may be rectangularly or hourglass shaped. The core 26preferably has two opposed faces, one oriented towards the backsheet 24and one oriented towards the topsheet 22.

Suitable materials for the core 26 include combinations of airfelt, suchas cellulose wadding, and fibrated communition pulp; layers of tissuepaper; and absorbent gelling materials. If a tissue paper core 26 isselected, tissue paper made in accordance with U.S. Pat. No. 4,191,609issued Mar. 4, 1980 to Trokhan and incorporated herein by reference toshow a particularly preferred tissue paper core construction for thesanitary napkin 20 described herein. If it is desired to incorporateabsorbent gelling materials into the core 26 of the sanitary napkin 20,absorbent gelling materials made in accordance with U.S. Patent Re.32,649 issued Apr. 19, 1988 to Brandt et al., and incorporated herein byreference for showing particularly preferred absorbent gellingmaterials, are suitable. A suitable laminate of absorbent gellingmaterials and tissue may be purchased from the Grain ProcessingCorporation of Muscatine, Iowa under Model Number L535.

The core 26 need not have a total absorbent capacity much greater thanthe total amount of bodily discharges to be absorbed. The core 26 ispreferably narrow and thin, to be comfortable to the wearer. For theembodiment described herein the capacity of the core 26 should be atleast about 2 grams of 0.9 percent saline solution. Suitable salinesolution is sold by Travenol Laboratories of Deerfield, Ill.

The core 26 should be sized to register with the topsheet 22 andbacksheet 24. The core 26 is preferably interposed between the topsheet22 and backsheet 24 to prevent the absorbent material of the core 26from shredding or becoming detached while the sanitary napkin 20 is wornand to ensure proper containment of bodily discharges. This arrangementalso helps to provide for a unitary assembly.

The sanitary napkin 20 preferably has a caliper of less than about 4millimeters and more preferably less than about 2 millimeters, asmeasured with a comparator gage having an approximately 80.0 gram testweight, an approximately 10.0 gram comparator foot having a diameter ofabout 2.54 centimeters and a contact surface area of approximately 5.1square centimeters. Also, the sanitary napkin 20 of the presentinvention should have a topsheet 22 surface area of at least about 100square centimeters to prevent discharged fluids from missing the targetarea.

The core 26 is preferentially joined to the topsheet 22, and may bejoined to the backsheet 24. Joining is preferentially accomplished byadhesive bonding the core 26 to the topsheet 22 or the backsheet 24.Such adhesive (not shown) may be applied in any suitable spray pattern,such as a spiral or longitudinally oriented beads. The adhesive shouldbe surfactant resistant and of low pressure sensitivity, so as not tostick to the skin of the wearer.

The sanitary napkin 20 also comprises a flap 28 extending from alongitudinal side margin 30 of the sanitary napkin 20, and preferablyone flap 28 extending from each longitudinal side margin 30 of thesanitary napkin 20. The flaps 28 have a proximal end 36 which istypically coincident with the juncture of attachment of the flap 28 tothe longitudinal side margin 30 of the sanitary napkin 20 or,alternatively, the proximal end 36 of the flap 28 may be joined to thesanitary napkin 20 at any other location juxtaposed with thelongitudinal side margin 30. The flaps 28 extend laterally outwardlyfrom the sanitary napkin 20 and terminate at a distal end 38 whichrepresents the point of the flap 28 furthest from the longitudinal axis34 of the sanitary napkin 20. The flaps 28 may be of any shape desired,with one preferred shape being shown in FIG. 1.

The flaps 28 are laterally outboard of the longitudinal centerline 34and central portion of the sanitary napkin 20. As used herein the phrase"central portion" refers to that part of the sanitary napkin 20intermediate, particularly laterally intermediate, and defined by theproximal ends 36 of the flaps 28.

The flaps 28 may be comprised of an integral and contiguous extension ofthe topsheet 22, the backsheet 24, or a laminate of both. Alternatively,the flaps 28 may be made of 9 separate and independent piece of materialjoined to the longitudinal side margin 30 of the sanitary napkin 20.

Each flap 28 has one face generally coextensive of the topsheet 22 and amutually opposed face generally coextensive of the backsheet 24. Facesare considered to be coextensive of the topsheet 22 or backsheet 24 if aline having a lateral component can be drawn from the central portion ofthe topsheet 22 or the backsheet 24 respectively, crosses a side margin30 or 32 at the perimeter of the sanitary napkin 20, and intercepts suchface.

The flaps 28 preferably have a means 40 for attaching one face of theflap 28 to the wearer's undergarment or to the other flap 28. Theattachment means may be pressure sensitive adhesive 40. If pressuresensitive adhesive 40 is selected, it should be disposed on the face ofthe flap 28 generally coextensive of the backsheet 24 so that when theflaps 28 are wrapped around the crotch portion of the wearer'sundergarment, the adhesive 40 will contact the outside of the wearer'sundergarment. A generally rectangular patch of adhesive 40 on each flap28, about 25 millimeters ×20 millimeters in size works well. Suitablepressure sensitive adhesive 40 is sold by the Anchor Continental, Inc.,3 Sigma Division of Covington, Ohio as 0.02 millimeter pass with CenturyAdhesive A305-4.

For packaging, including shipment and sale, the flaps 28 are folded overthe topsheet 22 so that the flaps 28 are in a disposition having thetopsheet facing relationship of FIGS. 1-5. The flaps 28 are consideredto be in a topsheet facing relationship if a line generallyperpendicular to the plane of the sanitary napkin 20 is drawn outwardlyfrom the topsheet 22 and intercepts either face of the flap 28. Theflaps 28 are preferably folded about the longitudinal lines generallycoincident the proximal edges 36 of the flaps 28, so that the maximumarea of the topsheet 22 may be covered by the flaps 28. This provides alarger area of the topsheet 22 which is protectively overlaid by theflaps 28, and particularly the area of the topsheet 22 which isgenerally registered with the wearer's vagina, so that a sanitary andclean appearance and condition of the topsheet 22 is maintained. It isnot necessary that the flaps 28 be folded about the line generallycoincident the proximal edge 36, that the flaps 28 be in contactingrelationship with the topsheet 22, or that no other folds between thedistal and proximal ends 36 and 38 of the flaps 28 occur. It is onlynecessary that the flaps 28 face towards and cover the topsheet 22, helpprevent outside contamination from readily soiling the portion of thetopsheet 22 covered by the flaps 28 and the flaps 28 are manipulable tobe readily unfolded by the wearer as the sanitary napkin 20 is installedin her undergarment.

Folding the flaps 28 in the configuration of FIG. 1 exposes the patch 40of adhesive on the face of the flaps 28 generally coextensive of thebacksheet 24. To prevent contamination and blocking of this patch 40,the adhesive patch 40 of each flap 28 may be covered with a separate anddedicated piece of release strip 46.

The various embodiments of release strips 46 described herein may beadvantageously made of kraft paper, calendered paper, or any othermaterials well known in the art for such purpose. Machine glazed ormachine finished paper having a basis weight of about 40.7×10³ kilogramsper square meter (25 pounds/3,000 square feet) works well. However, theinvention disclosed and claimed herein is by no means limited to anyparticular material selection.

Preferably the face of the release strip 46 which contacts the adhesivepatches 40 has a release coating, such as silicone, to easily facilitatethe removal of the release strip 46 from the flaps 28. Suitable releasecoatings are marketed by Akrosil of Menasha, Wis. as Silox 4R/0 and asSilox C1S.

If desired, the outwardly oriented face of the release strip 46 mayfurther comprise indicia, such as advertising or wearer instructions,thereon. The use of indicia is even more advantageous with the unitaryrelease strip 46' of FIG. 2, because of the increased visual impactpresented by the larger surface area of such unitary release strip 46'.

Furthermore, the sanitary napkin 20 is preferably provided with a meansfor maintaining the flaps 28 in the topsheet facing relationship of FIG.1 during packaging and prior to first use by the wearer. As used hereinthe "first use by the wearer" refers to the initial installation of thesanitary napkin 20 into the undergarment, so that the sanitary napkin 20may begin to perform the intended function of collecting vaginaldischarges.

One suitable means (not shown) for maintaining the topsheet facingrelationship comprises a small patch of adhesive disposed on the face ofeach flap 28 generally coextensive of the topsheet 22. By contactingthis face of the flap 28 against the topsheet 22, the adhesive willadhere the flap 28 to the outwardly oriented face of the topsheet 22until the flap 28 i s detached by the wearer or premature, undesiredseparation occurs. Any adhesive FDA approved for contact with human skinis suitable. The adhesive may be either hot melt or preferably waterbased latex. Suitable adhesives are sold by the Findley AdhesivesCompany of Columbus, Ohio under the Model Nos. L8082-02 and H2128-01.

Referring to FIG. 2, a more preferred means for maintaining the flaps 28in the topsheet facing relationship is a unitary release strip 46'adhered to each patch 40 of adhesive on the flaps 28 and bridging bothflaps 28. A component, such as a release strip 46', is considered"unitary" if it cannot be divided or disassembled without tearing orunintended gross separation. It is not necessary that a unitarycomponent be made of a single material but, rather that such componentcannot disassembled from and subsequently reassembled into the originalconfiguration. Components are considered to be "bridged" if they do notoverlap and are connectively spanned by an independent component.

This unitary arrangement provides the advantage that the flaps 28 cannotbe unfolded from the topsheet-facing relationship without detaching theunitary release strip 46' and, concomitantly advantageously, theadhesive patches 40 of the flaps 28 are covered.

Preferably, but not necessarily, the release strip 46', or at least theportion of the release strip 46' which bridges the flaps 28, islongitudinally bounded by the flaps 28. As used herein, a component orportion thereof is considered to be "longitudinally bounded" by theflaps 28 if such component or portion does not extend longitudinallyoutboard, i.e., away from the lateral centerline, of the flaps 28. Bybeing longitudinally bounded by the flaps 28, the release strip 46' isprevented from having substantial contact with the topsheet 22 whereadhesive attachment means are typically not disposed, and aneconomically advantageous conservation of material occurs.

It is important that the release strip 46' be conveniently and easilymanipulated by the wearer. This is because the sanitary napkin 20 isfrequently attached to the crotch of the wearer's undergarment when therelease strip 46' is to be removed. With a sanitary napkin 20 having aunitary release strip 46' according to this invention, the wearer cansee the flaps 28 in the advantageous topsheet facing relationship ofFIGS. 1 and 2,can see the release strip 46' while it is being removedand can further see the flaps 28 and adhesive patches 40 thereon whilethey are being manipulated into the wearing arrangement to which thewearer is accustomed. The wearer attaches the central adhesive 42 to thecrotch of her undergarment, peels off the release strip 46', typicallystarting at either lateral edge, folds the flaps 28 around the edges ofthe crotch of the undergarment, and attaches the flaps 28 to the outsideof the undergarment using the flap adhesive 40.

In yet another embodiment (not shown) a tricomponent release strip 46'may be utilized. Such a release strip 46' has components made from afirst material and which components are in contacting relationship witheach adhesive patch 40. The first material components are then joined bya different second material which bridges the first material componentsand thus the flaps 28. This arrangement provides the advantage that lessexpensive materials may be utilize in the release strip 46'.

In a variant embodiment of FIG. 2 (not shown) the unitary release strip46' may further comprise a means for initiating removal of the releasestrip 46' at or near its center, preferably at the longitudinalcenterline 34, rather than initiate removal at either lateral edge ofthe release strip 46'. This may be accomplished, for example, by anyappendage to the release strip 46' which enables it to be grasped nearthe longitudinal centerline 34 of the sanitary napkin 20. For example,the release strip 46' may be T-shaped in cross section having a tabwhich the user may grasp, or the release strip 46' may be looped uponitself to provide a double thickness of material which is not joinednear the longitudinal centerline 34, and only joined near the lateraledges of the release strip 46'.

Referring to FIG. 3, one nonlimiting variation of the aforementionedinvention is a sanitary napkin 20 having a unitary H-shaped unitaryrelease strip 46". This release strip 46" is preferably generallysymmetric about the longitudinal centerline 34, and the lateralcenterline of the sanitary napkin 20. The H-shaped release strip 46" hastwo substantially longitudinally oriented legs 46a" joined by a crossbar46b". The crossbar 46b", as described relative to FIG. 2, bridges and islongitudinally bounded by the flaps 28 and covers the adhesive patches40 joined to the outwardly oriented face of the flaps 28 generallycoextensive of the backsheet 24 either the crossbar 46b" or the legs46a" may wrap the longitudinal side margins 30 of the sanitary napkin20.

As illustrated by FIG. 4, this arrangement allows the legs 46a" of therelease strip 46" to overlay the outwardly oriented face of thebacksheet 24 and cover the adhesive strips 42 Joined to the centralportion of the backsheet 24. In this manner, a unitary release strip 46"performs the functions of maintaining the flaps 28 in the topsheetfacing relation, covering the adhesive patches 40 of the flaps 28, andcovering the adhesive patches 42 of the central portion of the backsheet24.

To install the sanitary napkin 20, the wearer merely unwraps the legs46a" of the release strip 46", exposing the backsheet 42 and theadhesive thereon. The wearer may then attach the central portion of thesanitary napkin 20 to the crotch of her undergarment, then detach thecrossbar 46b' so that the flaps 28 are free to be unfolded. The sanitarynapkin 20 may then be installed in the manner described above.

Referring to FIG. 5, in yet another embodiment, the means formaintaining the flaps 28 in the topsheet facing relationship comprisesmutually overlapping flaps 28 which are releasably affixed to eachother. Disposed on the face of one flap 28, which face is generallycoextensive of the backsheet 24, is a patch of adhesive 40'. The flap 28having such adhesive 40' is the first flap 28, of the two flaps 28, tobe folded over the topsheet 22 and is generally adjacent the topsheet 22while folded. The second flap 28 is folded over the first flap 28.

In this configuration, the adhesive 40' of the first flap 28 may contactthe face of the second flap 28 generally coextensive of the topsheet 22.It will be apparent that such adhesive 40' should be disposed on aportion of the first flap 28 which is overlapped by the second flap 28.In this manner, the opposed faces of each flap 28 are mutuallyreleasably affixed by such adhesive 40' and the flaps 28 are maintainedin the mutually overlapping, topsheet facing relationship. If desired,the adhesive 40' may be partially covered by a release strip (notshown).

Referring to FIG. 6, disclosed is an apparatus 100 and the associatedprocess for carrying out the claimed invention. It is to be recognizedthat similar apparatus and processes are known and have been used in theart of applying adhesive 42 to the backsheet 24 of a sanitary napkin 20having a conventional packaging disposition. More particularly,disclosed herein is a process for applying the adhesive 40 and releasestrip 46 to a sanitary napkin 20 provided in a generally flat,nonwrinkled disposition, with the flaps 28 prefolded into theaforementioned topsheet facing relationship, and the face of the flaps28 generally coextensive of the backsheet 24 exposed to the apparatus100.

The apparatus 100 comprises a conveyor 110, a means 112 for unwinding aroll of material 116; a means for cutting such material 116, such as arotary knife 102 and a stationary anvil 104; and a means fortransferring segments 118 of material 116 cut from the roll, such as arotary vacuum head 106. The rotary knife 102 and rotary vacuum head 106may be associated by and mounted on a rotating assembly 108. All of suchcomponents are synchronized to and used in conjunction with a productionassembly line having a conveyor 110 that transports the sanitary napkins20.

The apparatus is provided with a longitudinally trisectioned roll (notshown). As used herein a roll which is "longitudinally trisectioned" hasthree distinct zones, each laterally offset from the other. It will beapparent that the longitudinal direction of the roll of material 116need not be coincident with the longitudinal direction of the sanitarynapkin 20 to which a discrete segment 118 of the material from the rollis later applied.

The material 116 of the roll comprises any suitable release stripmaterial 40 and adhesive 46, such as those described above. Preferablythe parent material component of the roll comprises a release stripmaterial 46 having mutually opposed first and second faces. The firstface has two outboard trisections 122, each with a release coating, suchas the aforementioned silicone, thereon. The two outboard trisections122 are separated by a central trisection 124 intermediate the outboardtrisections 122. The central section 124 may or may not have a releasecoating, as desired.

Each outboard trisection 122 is further provided with longitudinallyoriented adhesive 40. The adhesive 40 may be continuous throughout theoutboard trisections 122 or may be intermittent, as desired. Theadhesive 40 may be applied by hot melting onto the roll 116 as it isunwound or, alternatively, the roll 116 may be precoated with theadhesive 40 prior to being wound into the rolled configuration. If thelatter arrangement is selected, the release strip material 46 of roll116 should be further release coated on the second face, so that theroll 116 does not stick to itself when the roll 116 is attempted to beunwound. Under either configuration, the release strip-adhesivecombination 46 and 40 is unitary as provided by the roll 116.

Preferably, the discrete segments 118 have a pitch corresponding to thelongitudinal dimension of the sanitary napkin 20. As herein "pitch"refers to the longitudinal distance between corresponding points ofadjacent sanitary napkins 20 as they are transported on the conveyor110. The conveyor 110 may be provided with a vacuum means (not shown)for temporarily holding the sanitary napkins 20 to the underside ofconveyor 110. In this configuration, the flaps 28 of the sanitarynapkins 20 may be downwardly folded over the topsheets 22 so that thefaces of the flaps 28 generally coextensive of the backsheet 24 areexposed.

It is to be recognized a sanitary napkin 20 may be joined to orseparated from the adjacent sanitary napkins 20 while on the conveyor110. Thus, depending upon the final trimming of the sanitary napkin, thesegments 108 cut from roll 116 may have a pitch less than or equal tothat of the pitch of the sanitary napkins 20.

The process of supplying and segmenting material 116 from the roll maybe accomplished by using the disclosed apparatus 100 as follows. Thematerial 116 is fed from the roll (not shown) through the tracking andV-rolls 126 to the stationary anvil 104. The rotating assembly 108comprises two oppositely disposed rotary knives 102 and two oppositelydisposed rotary vacuum heads 106, so that for each one-half rotation ofthe rotary assembly 108, a sanitary napkin 20 may be manufacturedaccording to the present invention.

Each rotary knife 102 and rotary vacuum head 106 is geared to the rotaryassembly 108 in a known fashion, so that the rotary knife 102 and rotaryvacuum head 106 face towards the conveyor 110 throughout the entirecycle. As the material 116 is fed to the stationary anvil 104, onerotary knife 102 cuts a segment 118 from the material 100. The segments118 are cut to a predetermined length by the rotary knife 102 dependentupon the rotation frequency of the rotary knife 102 and speed at whichthe material 116 is fed from the roll through the stationary anvil 104.The length of a segment 118 cut from the trisectioned roll 116preferably corresponds to the length of the segment 118 desired to beapplied to the finished product, as illustrated in FIG. 2.

The cut segment 118 is held in the proper longitudinal orientationrelative to the sanitary napkin 20 and transported from the stationaryanvil 104 to the conveyor 110 by the rotary vacuum head 106. The segment118 of adhesive 40 and release strip 46 is then generallycontemporaneously applied to the exposed faces of the flaps 28 generallycoextensive of the backsheet 24, so that the adhesive 40 of the cutsegment 118 is in contacting relationship with such faces.

It will be apparent to one skilled in the art that several variationsmay be made without departure from the spirit and scope of the claimedinvention. For example, asymmetric structures are possible, single flapsanitary napkins 20 are known in the art, and combinations of theaforementioned embodiments are feasible.

What is claimed is:
 1. A process for applying adhesive and release stripto a sanitary napkin having a liquid pervious topsheet, a liquidimpervious backsheet at least partially peripherally joined to saidtopsheet, an absorbent core intermediate said topsheet and saidbacksheet, two longitudinal side margins, and a flap extending outwardlyfrom each longitudinal side margin, each of said flaps having a facegenerally coextensive of said topsheet and a face generally coextensiveof said backsheet, said process comprising the steps of:providing saidsanitary napkin in a generally flat position; folding each of said flapsabout a line parallel to said longitudinal side margin so that at leasta portion of each of said flap faces that is generally coextensive ofsaid topsheet contacts at least a portion of said topsheet that directlyoverlies said core, said folding pattern exposing each of said flapfaces that is generally coextensive of said backsheet; providing alongitudinally trisectioned web of material comprising:a release striphaving opposed first and second faces, said first face having twooutboard trisections, each with a release coating thereon, a centraltrisection intermediate said outboard trisections, and twolongitudinally oriented adhesive segments, one overlying each saidoutboard trisection; cutting said trisectioned web of material to apredetermined length, and; generally contemporaneously applying saidadhesive and said release strip to said exposed faces of said flapsgenerally coextensive of said backsheet of said sanitary napkin withsaid adhesive in contacting relationship with said faces.
 2. The processaccording to claim 1 wherein said release strip is release coated onsaid second face.
 3. The process according to claim 1 wherein saidadhesive is applied to said outboard trisections of said release stripby hot melting the adhesive onto said release strip.
 4. The processaccording to claim 1 wherein said adhesive is substantiallylongitudinally continuously applied to said release strip.
 5. Theprocess according to claim 1 wherein said adhesive segments have a pitchcorresponding to, and said release strip is cut to a lengthcorresponding to, the longitudinal dimension of said sanitary napkin. 6.The process according to claim 1 wherein said adhesive segments have apitch less than the longitudinal dimension of said sanitary napkin.